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Framed for strength a problem when the stairs are at one end of the deck rather than someplace in the middle. We feel comfortable making the argument that only the walkable stringers need to be attached with code-compliant hangers. The extra outer stringer, then, can be thought of as support for stiffening the railing posts and as a provision for solid nailing when attaching the treads, risers, and trim. Sister to increase the span. Notched 2x12 stringers have a maximum span of 6 ft. If approved by your inspector, however, this span can be extended by nailing 2x stiffeners to the uncut portion of each stringer. and treads then becomes much easier, and it takes a back seat to other priorities. As long as you stay within the code minimums and maximums, you’re now free to lay out the riser height and tread width at whatever measurements feel comfortable, make the math simplest, combine to yield a stringer that fits in the rough space you’re aiming to fill, or make the best use of the tread and riser material. Strategies for strength Although there are no provisions in the building code for interior stair-stringer spans and methods of attachment, deck stairs have guidelines (see “Know the code,” p. 67). It’s not surprising that many builders get this wrong, because with notched stringers, the maximum span is only 6 ft. measured horizontally. If you’re just over that distance (as we were on this project), check to see if your code official will allow additional stringers and/or sistering additional lumber to the conventional 2x12 stringers as a means of providing extra rigidity without adding midspan posts and footings. Regardless of span issues, there are a couple of good reasons for cutting one or two extra stringers. The code-required hardware used to attach the upper end of a stringer to the deck has a minimum setback from the end of the dropped rim, which can be 68 FINE HOMEBUILDING Plan for repairs, and always promote drying Traditionally, the 2x4 cleat at the bottom of a staircase nests into notches in the front edge of each stringer. The purpose of this cleat is to anchor the staircase to the landing or pad so that the stringers won’t slide out of position. Although unconventional, moving the cleat to the back of the staircase has a couple of benefits. First, it leaves more room to attach the lowest guardrail post. Second, you have easy repair access if the cleat rots— a strong possibility when a piece of lumber, even a pressure-treated board, is in constant contact with concrete that has limited exposure to light and air. If the cleat needs to be replaced, the work can be done from the back without removing risers and treads. Cut through the nails that hold the cleat to the stringers, and then cut the cleat into pieces to remove it from the wedge bolts. One other detail that helps to prevent the exposed end grain of the stringers from sucking up moisture from the concrete is to provide them with a gap. To do this, cut the notch for the 11⁄2-in.-thick cleat to a depth of Subassembly Prefab, then set. If you cut the stringers carefully, you can assemble them, set them into the awaiting hangers as one unit, and know that the treads and risers will be aligned well.